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+.. BSD LICENSE
+ Copyright(c) 2017 Intel Corporation. All rights reserved.
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ * Neither the name of Intel Corporation nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Service Cores
+=============
+
+DPDK has a concept known as service cores, which enables a dynamic way of
+performing work on DPDK lcores. Service core support is built into the EAL, and
+an API is provided to optionally allow applications to control how the service
+cores are used at runtime.
+
+The service cores concept is built up out of services (components of DPDK that
+require CPU cycles to operate) and service cores (DPDK lcores, tasked with
+running services). The power of the service core concept is that the mapping
+between service cores and services can be configured to abstract away the
+difference between platforms and environments.
+
+For example, the Eventdev has hardware and software PMDs. Of these the software
+PMD requires an lcore to perform the scheduling operations, while the hardware
+PMD does not. With service cores, the application would not directly notice
+that the scheduling is done in software.
+
+For detailed information about the service core API, please refer to the docs.
+
+Service Core Initialization
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+There are two methods to having service cores in a DPDK application, either by
+using the service coremask, or by dynamically adding cores using the API.
+The simpler of the two is to pass the `-s` coremask argument to EAL, which will
+take any cores available in the main DPDK coremask, an if the bits are also set
+in the service coremask the cores become service-cores instead of DPDK
+application lcores.
+
+Enabling Services on Cores
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Each registered service can be individually mapped to a service core, or set of
+service cores. Enabling a service on a particular core means that the lcore in
+question will run the service. Disabling that core on the service stops the
+lcore in question from running the service.
+
+Using this method, it is possible to assign specific workloads to each
+service core, and map N workloads to M number of service cores. Each service
+lcore loops over the services that are enabled for that core, and invokes the
+function to run the service.
+
+Service Core Statistics
+~~~~~~~~~~~~~~~~~~~~~~~
+
+The service core library is capable of collecting runtime statistics like number
+of calls to a specific service, and number of cycles used by the service. The
+cycle count collection is dynamically configurable, allowing any application to
+profile the services running on the system at any time.